The history of the theory of knowledge confronts us with what appears to be a perpetual "frontier" mentality. No matter how exhaustive or ramified its previous philosophical labors may have been, it seems forever bent on testing the need for still another beginning. That is as true today as it ever was during the period of nearly constant innovation running from Descartes to Kant to Hegel. You have only to think of the startling frequency with which theorists continue to believe themselves to be initiating entirely new beginnings or, finally, to be correcting the hopeless conceptual errors and inadequacies of all past canons. Think, for instance, of Edmund Husserl's Cartesian Meditations (1960) or W.V. Quine's "Epistemology Naturalized" (1969); or, more adventurously, Michel Foucault's Nietzscheanized genealogies (1977) or Paul Churchland's would-be elimination of the entire "folk" conception of epistemology (1989).